The father of a student who was having a “serious mental health relapse” said he was afraid of his son's behaviour in the hours before he lit a fire that killed his grandmother. 

Chanatorn Croghan, known as Marco, was aged 19 when he started the fire at 89-year-old Vera Croghan’s home on Unthank Road, Norwich, in December 2020. 

He admitted manslaughter by diminished responsibility and arson and was detained indefinitely in hospital. 

A three-day inquest into Mrs Croghan's death, being held at Norfolk Coroner’s Court this week, heard from Marco’s father, Richard Croghan.

Vera Croghan (Image: Supplied by family)

He explained that he had called police in the hours before the tragedy after Marco’s demeanour changed quickly and suddenly “out of the blue”. 

His son had been watching television with Mrs Croghan before she retired to bed, but then became caught up in a conversation with his father about using his phone. 

Mr Croghan said: “That evening, he appeared blank, expressionless, [had] no concept of thought – like talking to a cat.  

“His body language – pure aggression came out – it made me very frightened, so I called the police. 

“He made me really frightened.”

He added: "I was terrified for my life."

Mr Croghan said he called 999 just before midnight and remained on the phone until officers arrived.  

He said he was “shell-shocked” when told by officers that they “couldn’t do anything because no crime had been committed”. 

Vera Croghan's house on Unthank RoadVera Croghan's house on Unthank Road (Image: Newsquest)

When the police left, Mr Croghan also left the house because he “feared for his life”. 

He did not wake his mother, who remained asleep in bed, as he said his son had never shown aggression to her. 

He added: “It never occurred to me that he was going to set a fire.” 

The inquest continues, with police bodycam footage of the officers’ visit to the home due to be played to the court.